Waste pickle liquor disposal



May 30, 1944.

E. C. CARLSON ETAL WASTE PICKLE LIQUOR DISPOSAL Filed Jan. 22. i942INVENTORS. 54/?! f. (flaw/Va flax/ M5 fab 4 9 together .while the pump.and oi a smooth arate pipes arranged to bring the Patented May 30, 1944ws's'rs m Lmuon DISPOSAL p Earl c. Carlson, Pittsburgh, and Douglas-F.

Sharp, New Kensington, Pa.

Application January 22, 1942, Serial No. 427,841

3 Claims; (c1. zi -2) This invention is concerned with the problem ofneutralizing waste pickle liquor with a-basic solution to render theliquor flt for disposal, the object being to do this in an economicalmanner so as to produce a smooth mixture capable of being pumped througha pipe to disposal equipment.

Waste pickle liquor results from the practice otpickling steel liquor;usually a products with an acid pickle sulphuric. acid solution ofsumcient strength to remove oxides from the steel.

This liquor becomes a waste product when its metallic salt contentincreases and its acid content decreases to points whergpickling becomesuneconomically'slow. This waste product must then be neutralizedsinceits acid content is still too high to otherwise permit its disposl. 1

According to-the prior art, this neutralization is eflectedby mixing thewaste pickle l q or with a lime suspension in tanks, the mixture beingagitatedto promote the necessary reaction. The waste pickle liquorcontains various impurities and is a rather complex product, largevolumes of intermediate-products being i'ormed during theneutr'alization'which precipitate to form a heavy sludge. In addition,clots and :heavy lumps are i'ormed when the lime suspension is mixedwith the waste pic e liquor. As a result otthese complications, it isnecessary to unduly prolong the agitation of the procedure. possible tomixture if the reaction is 'to be carried to completion. In actualpractice an excess of lime is usedin an effort to shorten the agitationperiod, but

together closelyadiacent the central portion of the pumps impeller.

It has been found that the mixture resulting from the above has a theproper amounts of the waste pickle liquor and the'line suspension areused to just effect complete neutralization. The viscosity lowers whenthere is an excess either of the liquor or of the basic solution.Thereforethe above proce dure permits very nice proportioning of the twomaterials, the separate flows being'regulated as required to produce aproduct of maximum viscosity. The proportioning may be convenientlycarried out by observing the working load on the pump, the relativevolumes of the liquor and of the'basic solution brought together beingproportioned to place a maximum working load on the lustrates acentrifugal pump of the type adapted to carry out the present invention;

peller l, suitably pension until they are is sumciently smooth inconsistency "to permit its being 1) ped through a pipe withoutdifllcuity. According to the present invention, these objectionablefeatures of the prior art practice are eliminated by feeding separatedflows of the waste pickle liquor andthe basic'solution, such.

central intake as the lime suspension. into the p of a centrifugalpumpan there bringingthem is working so they are violently intermixedcoming together. Ullder ythese conditions the mixturereactsi-withoutlumping or clotting and is-iorced by th :v pumpthroughits discharge as a substantially neutral product fit for disposalconsistency which can. be

immediately upon their More specifically, waste pickle liquor conduit l,and a valved lime suspension line 2, both leading tothe (central intake3 of a centrifugal pump having an imdriven at high speed, and anoutlet"5. A valved water inlet 6- is provided for the purpose of primingthe pump at the start of operations. It is to be noted that the conduitsi and 2 both open directly at the central intake 3 ot the pump, on thesame side or itsdmpeller 4, and that the two continue to completelyseparate the waste pickle liquor and the lime susbrought together atthisintake. -The load on. the impeller 4 may be measured by anysuitabletorque .measuring de- 5 vice. p

pumped through apipe without difllculty. Any 5 centrlfugalpump may beused providingthe tveo materials are fed to its central intake byseptwo. materials 5 "with a. basic solution to render the. liquor fitdisposal, said method being characterized trii'ugal pump whilethe pumpis working so they are violently gather; the mlxhire we em 1 l 1. Amethod of neutralizing waste pickle liquon terfeedingseparated flows ofthe liquor and basic solution into the central intake or. a cen andthere bringing them together intermixed immediately u on their ming 'to-I reacting without umping or clotting and beingiorced by the pumpthrough its discharge to creates smooth flow of a substantially neutralproduct'flt for 2. Amethod of I withv a basic solution render the liquorn; ior disposal, said method bemg characte maximum viscosity when thisdrawing shows a valved neuttirlizing waste'pickle liquor by the mixturereacting and being forced by the pump through its discharge to create asmooth flow of a substantially neutral product fit for disposal, therelative volumes of the liquor and ot the basic solution broughttogether being proportioned to place a maximum working load on the pump.

3. A method of neutralizing waste pickle liquor with a basic solution torender the liquor fit for disposal,- said method bein characterized byfeeding separated flows of the liquor and the basic solution into thecentral intake of a centrifugal pump and there bringing them togetherwhile the pump is working so they are violentl intermixed immediatelyupon their coming together,

the mixture reacting without lumping or clotting and being forced by thepump through its discharge to create a smooth flow of a substantiallyneutral product lit for disposal, the relative volumes of the liquor andof'the basic solution brought together being proportioned to produce aproduct of maximum viscosity.

EARL c. CARLSON. DOUGLAS F. SHARP.

